The present invention is directed to snowboard devices and, more particularly, to a snowboard boot, binding or other rider interface with an upper portion, such as a leg interface, that translates and rotates relative to a lower portion, such as a foot interface.
Snowboarders usually stand on the snowboard facing generally perpendicular to the longitudinal axis of the snowboard. To accomplish various maneuvers on the snowboard, the snowboarder must often shift his or her center of gravity forward or rearward in the long direction of the snowboard. This usually requires the snowboarder to be able to pivot his or her legs from side to side around the ankle. Various schemes are known to allow snowboarders to pivot their legs sideways. For example, DE 3,622,746 shows a binding with upper and lower sections that pivot around a longitudinal axis of the binding. U.S. Pat. No. 5,401,041 shows a boot with an upper leg section, a lower heel section and a pivot coupling between the upper leg section and the lower heel section, wherein the upper leg section pivots relative to the lower heel section around a longitudinal axis of the boot. Finally, U.S. Pat. No. 5,771,609 shows a boot similar to the boot shown in U.S. Pat. No. 5,401,041 but with the upper leg section and the lower heel section being formed as an insert between flexible inner and outer linings.
The applicant discovered that boots that pivot around a single fixed axis do not really accommodate the anatomical motion required for effective weight transfer on the snowboard. That is because rolling of the heel often accompanies articulation of the ankle during snowboard maneuvers, thus resulting in a more complex overall motion of the leg. Thus, there is a need to make a snowboard boot that accommodates such motion.
The present invention is directed to a snowboard interface that more closely accommodates the anatomical motion required to articulate the legs from side to side relative to the snowboard. In one embodiment of the present invention, a snowboard interface has an upper interface and a lower interface, wherein the upper interface rotates and translates relative to the lower interface. More specifically, the snowboard interface includes a foot interface, a leg interface and a coupling mechanism for coupling the leg interface to the foot interface so that the leg interface translates sideways and rotates sideways relative to the foot interface. In an even more specific embodiment, the coupling mechanism includes a leg coupling member coupled to the leg interface and a foot coupling member coupled to the foot interface. The leg coupling member moves relative to the foot coupling member, and a guide mechanism is provided for guiding the movement of the leg coupling member relative to the foot coupling member so that the leg coupling member translates and rotates relative to the foot coupling member.
In one form of the guide mechanism, a guide surface is disposed on one of the leg coupling member and the foot coupling member, and an outer peripheral surface is disposed on the other one of the leg coupling member and the foot coupling member so that the outer peripheral surface rolls on the guide surface when the leg coupling member moves relative to the foot coupling member. As a result, a pivot location follows the area of contact between the guide surface and the outer peripheral surface.
In another form of the guide mechanism, a first guide projection extends from one of the leg coupling member and the foot coupling member and a first slot is formed in the other one of the leg coupling member and the foot coupling member, wherein the first guide projection extends into the first slot. To provide additional variation on the movement of the leg coupling member relative to the foot coupling member, the first slot may have a varying width. To fine tune the movement of the leg coupling member relative to the foot coupling member, a second guide projection may extend from one of the leg coupling member and the foot coupling member and a second slot may be formed in the other one of the leg coupling member and the foot coupling member, wherein the second guide projection extends into the second slot. The first guide projection and the first slot cooperate with the second guide projection and the second slot to provide a compound motion of the leg interface relative to the foot interface.